1. Field of the Invention
The present invention relates to a dyeing method of dyeing a plastic lens, a dyeing device, and a dyeing jig.
2. Description of Related Art
Conventionally, a dip dyeing method has been adopted in most cases as one of dyeing methods of dyeing plastic lenses for spectacles. This dip dyeing method includes: preparing a dyeing solution by mixing disperse dyes of primary colors of red, blue, and yellow and dispersing the mixture in water; heating the dyeing solution to about 90xc2x0 C.; and dipping a plastic lens into the heated solution, thereby dyeing the lens.
As an alternative to the dip dyeing method, there has been proposed a vapor-deposition dyeing method. This method includes heating sublimatable solid dye under vacuum to sublimate and vapor-deposit the sublimated dye onto a plastic lens which is heated simultaneously under vacuum, thereby dyeing the lens.
The conventional dip dyeing method and vapor-deposition dyeing method, however, has the disadvantages that it is difficult to provide a stably dyed lens. In particular, it is difficult to dye a lens of low dyeability or to dye a lens in deep colors, or in colors of high density. Furthermore, it is desired to more easily and effectively dye a lens.
The present invention has been made in view of the above circumstances and has an object to overcome the above problems and to provide a dyeing method, a dyeing device, and a dyeing jig, capable of easily and effectively dyeing a plastic lens and also stably dyeing various lenses in various colors.
Additional objects and advantages of the invention will be set forth in part in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the purpose of the invention, there is provided a dyeing method of dyeing a plastic lens, including: a step of placing the lens in a predetermined position in a vacuum vapor-deposition device; a step of placing base bodies to be used for a dyeing operation in the vapor-deposition device, each of the base bodies being applied with dyeing solutions each containing a dissolved or fine-grained dispersed sublimatable dye to form a dye application area on each base body, and the base bodies being arranged in opposite positions to each other with respect to the lens so that the dye application area faces each surface of the lens without contact therewith; and a step of heating the base bodies by heat sources under vacuum in the vapor-deposition device, thereby sublimating the dye of the dye application areas to vapor-deposit the sublimated dye on the lens.
According to another aspect of the present invention, there is provided a dyeing device for dyeing a plastic lens, including: a lens holding unit for placing the lens in a predetermined position in the device; a base body placing unit for placing base bodies to be used for a dyeing operation in opposite positions to each other with respect to the lens, each of the base bodies having a dye application area applied with dyeing solutions each containing a dissolved or fine-grained dispersed sublimatable dye, so that the dye application area faces each surface of the lens without contact therewith; a vacuum pump for creating an almost vacuum in the device; and a heating unit for heating the base bodies placed in the opposite positions to each other with respect to the lens.
According to another aspect of the present invention, there is provided a dyeing jig for dyeing a plastic lens, including a lens holder for holding a peripheral portion of the lens; and a base body retainer for placing base bodies to be used for a dyeing operation in opposite positions to each other with respect to the lens, each of the base bodies having a dye application area applied with dyeing solutions each containing a dissolved or fine-grained dispersed sublimatable dye, so that the dye application area faces each surface of the lens without contact therewith.